It would depend on what kind of portable player. Many portable can play CD and DVD. If it had the function to let you play music than .mp3 are the most common format.
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portable media player
Click on the app and buy it or play the songs u want to play
A car player means that the player is built into the car. A portable DVD player can only be played in the car by connecting a DV-power cable to the car battery.
I would have to say the Archos portable media player would be the best choice for this question. This particular media player has the ability to synchronize with cable or satellite provider in order to schedule and record television shows. By having this capability this allows the Archos to have as many television stations as your cable or satellite provider. In other words, the stations you have available on your regular television model will be exactly the same amount that will be available to you on your Archos media player.
This one is great. I'm unsure of the name but here it is http://www.alybuy.com/Portable-Digital-Media-Center-DVD-CD-MP3-MP4-Video-Game-Player.1906
No. Windows Media player can't play mkv files.
Movie actually can play in many player Example:Windows Media Player,Media Player Classic and etc.
It is any media file, Windows Media Player can play.
No. You do not have to install Windows Media Player to play online video games.
One player I know is Windows Media Player
Windows media player.